Theoretical Probability Statistics Example 4

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Example 4

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Two fair six-sided dice are rolled. What is the theoretical probability that the sum is 7?

Solution

  1. 1
    Step 1: The favourable outcomes are (1,6), (2,5), (3,4), (4,3), (5,2), and (6,1), so there are 6 favourable outcomes.
  2. 2
    Step 2: There are 6ร—6=366 \times 6 = 36 equally likely outcomes in total, so the probability is 636=16\frac{6}{36} = \frac{1}{6}.

Answer

16\frac{1}{6}
Theoretical probability uses the full sample space of equally likely outcomes. Listing combinations carefully helps avoid missing or double-counting outcomes.

About Theoretical Probability

Theoretical probability is the expected probability of an event calculated by mathematical reasoning about equally likely outcomes, without conducting experiments. It equals the number of favorable outcomes divided by the total number of possible outcomes.

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